body{
  background-color: #f5f8f9;
  position: relative;
}
.center-wrap {
  width:1520px;
  margin:0 auto;
}
.clearfix {
  overflow: hidden;
}
.clearfix::after {
  content: '';
  display: block;
  clear: both;
  overflow: hidden;
}
.db {
  display: block;
}
.dib {
  display: inline-block;
}
.tac {
  text-align: center;
}

